Annotated Bibliography
The article “Pneumococcal Disease and the Effectiveness of the PPV23 Vaccine in Adults: A Two-Stage Bayesian Meta-Analysis of Observational and RCT Reports” by Latifi-Navid, H., Latifi-Navid, S., Mostafaiy, B. et al. (2018) focuses on the controversy around the efficacy of PPV and PCV in an attempt to determine whether they are effective against invasive and non-invasive pneumococcal infections. According to the authors, the different opinions that exist concerning PVP and PCV’s is because of the result obtained from observational studies and that retrieved from randomized control trials.
Despite the controversy however, the authors provide an analysis of the processes that are involved when managing invasive and non-invasive pneumococcal infections in an informative matter that helps the audience understand the impact of PVP and PVC in managing pneumococcal infections. According to the authors, PPVs have evolved from 2-valent vaccines used in the 1980’s to the most recent vaccine which is the PPV-23. The authors further argue that PPVs are ideal for people in the ages of 65 or older and also adults at a high risk of contracting invasive pneumococcal diseases. This include individuals with a history of Chronic renal failure, diabetes mellitus, heart failure, chronic lung disease and sickle cell diseases. The authors successfully interpret the data collected during their research to draw the conclusion that PPVs and PCVs are efficient enough to protect adults in the ages of 65 and above against invasive and non-invasive pneumococcal infections.
Berical C, Cruz D, Harris D and Possick D, (2016) “Pneumococcal Vaccination strategies: an update and perspective” Annals of the American Thoracic Society, 13(6): 933–944.
doi: 10.1513/AnnalsATS.201511-778FR
The article focuses on the impact that the immune system has in determining the efficiency of PPVs and PCVs when protecting against invasive and non-invasive pneumococcal infections. According to the conclusion drawn by the authors, PPVs have proven effective in helping to lower the rate of invasive pneumococcal disease. Their efficiency is however lower when used to reduce the rate of pneumonia in patients or in lowering the overall mortality rate. The authors further argue that immunocompromised individuals, or people with an impaired immune system are less likely to experience positive results when using PPV and PCV vaccinations compared to immunocompetent individuals, or people with a normal immune system.
The information discussed in the article reveals that the efficiency of PPVs and PCVs in preventing or reducing invasive and non-invasive pneumococcal infections decreases as people age. According to Berical et al (2016), PPV and PCV for an immunocompetent patient who is 80 years old have a 67 percent chance of preventing pneumococcal infections when the vaccination is administered within three years but the efficiency drops to 32 percent 5 years after the vaccination occurs. Despite the decline in efficiency of the vaccines over time, the authors argue that PPVs are effective in preventing pneumococcal infections among people aged 65 years or older. The paper has credibility in that, the conclusions made are drawn from research conducted by the Community Acquired Pneumonia Immunization Trial in Adults on students to assess the different levels of efficiency for PPVs and PCVs between vaccine type and non-vaccine type infections.
Gu W, Li J, Wang Y, Wang Y, Wang Y and Zhu F (2018) “Effectiveness and practical use of 23-valent pneumococcal polysaccharide vaccine in healthy and special populations” Human Vaccines and Immunotherapeutic” 14(4): 1003–1012. Doi: 10.1080/21645515.2017.1409316
Gu et al (2018) draw the conclusion that PPVs and PCVs are efficient for helping protect adults aged 65 and older from invasive and non-invasive pneumococcal infections. Their findings are drawn from data collected from various sources such as a study conducted in Japan to assess the immunogenicity and whether it is safe to revaccinate individuals in different stages. The authors analyse and interpreted data to draw the conclusion that revaccination of PPV is tolerable among patients aged 65 and above. Despite its efficiency however, PPV has had mixed results when it comes to prevention of community acquired pneumonia and Laboratory confirmed non-bacteraemia pneumococcal pneumonia.
The authors further argue that PCV vaccinations have a 45 percent chance of preventing laboratory confirmed non-bacteraemia pneumococcal pneumonia among people in the ages of 65 or older. Furthermore, PPVs have proven effective in preventing hospitalization for patients with non-bacteraemia pneumococcal pneumonia with an efficacy rate of 48 percent. The authors also correct claims made by other researchers in the past which suggest that PPV’s are generally weak when used to protect against pneumonia. They argue that the information used to support such claims is based off of data collected through questionable diagnostic methods and therefore not credible. This is especially because data collected by the authors reveal that PPVs help to reduce bacteraemia pneumococcal pneumonia, non-bacteraemia pneumococcal pneumonia and invasive pneumococcal disease by 74, 54 and 80 percent respectively.
Kioumis P and Pitsiou G, (2011) “Pneumococcal vaccination in adults: does it really work?” Elsevier, retrieved from, https://doi.org/10.1016/j.rmed.2011.07.008
The article by Kioumis and Pitsiou (2011) adds on to existing information suggesting that PPVs and PCVs are efficient in assisting adults aged 65 years or older avoid invasive and non-invasive pneumococcal infections. The authors point out the significant impact that PPVs and PCV have had on pneumococcal infections. The use of PPV-7 for example helps to tremendously lower invasive infection among children and further lowers the rate of pneumococcal infections among people aged 60 or older. Furthermore, PCVs have proven effective in lowering the level of nasopharyngeal carriage of stereotypes that are present when the vaccine is administered. Reducing the attenuation of the carrier rate for instance lowers the likelihood that the infection will be transmitted to non-carriers and also then risk that the patient will contract other subsequent diseases as a result. According to the authors, the PCVs induce a state of herd immunity which is achieved when a significant number of the population in a community is immunized and ends up reducing the chances of the disease from spreading to individuals in the same community who are not vaccinated.
The information provided by Kioumis and Pitsiou (2011) further explains how reliance on PCVs has helped to reduce the occurrence of pneumococcal diseases but have also played a role in lowering the prevalence of invasive pneumococcal diseases and also lowering the rate of respiratory tract infections among adults in the ages of 65 and above. However, the authors present the case that the efficiency of PCVs is affected by non-PCV stereotypes either included in PVPs or those that are lacking in both PCV and PPV vaccines. Despite this however, the authors draw the conclusion that PPVs and PCVs are adequate enough to help people in the age of 60 and above protect themselves against pneumococcal infections.
Fry K, Ladhani N, Ramsay E and Sheppard C, (2019) “Effectiveness of 23-Valent Polysaccharide Pneumococcal Vaccine and Changes in Invasive Pneumococcal Disease Incidence from 2000 to 2017 in Those Aged 65 and Over in England and Wales” The Lancet, retrieved from, https://doi.org/10.1016/j.eclinm.2018.12.007
Fry et al (2019) are of the opinion that; although PPVs and PCVs are effective in protecting people aged 65 years and above from pneumococcal infections, their efficiency is affected by the duration of time since the patient was vaccinated. Individuals who are vaccinated within two years have a 41 percent chance of not contracting the infections. The efficiency however drops to 34 percent for those vaccinated in the duration of between 2 to 4 years and 23 percent for those vaccinated for five or more years prior. The authors further argue that although the efficiency of the vaccine is not significantly affected by the patient’s age, the vaccines are more efficient when given to individuals who lived healthy lives prior to contracting the pneumococcal infection.
Furthermore, although PVPs do not offer significant protection when dealing with vaccine related stereotypes, they were responsible for reducing the number of invasive pneumococcal diseases among patients aged 65 and above by 15 percent. The conclusions drawn from the data collected reveal that PCVs and PPVs are efficient in helping individuals in the ages of 65 and above against invasive and non-invasive pneumococcal infections.
References
Berical C, Cruz D, Harris D and Possick D, (2016) “Pneumococcal Vaccination strategies: an update and perspective” Annals of the American Thoracic Society, 13(6): 933–944.
Doi: 10.1513/AnnalsATS.201511-778FR
Fry K, Ladhani N, Ramsay E and Sheppard C, (2019) “Effectiveness of 23-Valent Polysaccharide Pneumococcal Vaccine and Changes in Invasive Pneumococcal Disease Incidence from 2000 to 2017 in Those Aged 65 and Over in England and Wales” The Lancet, retrieved from, https://doi.org/10.1016/j.eclinm.2018.12.007
Gu W, Li J, Wang Y, Wang Y, Wang Y and Zhu F (2018) “Effectiveness and practical use of 23-valent pneumococcal polysaccharide vaccine in healthy and special populations” Human Vaccines and Immunotherapeutic” 14(4): 1003–1012. Doi: 10.1080/21645515.2017.1409316
Kioumis P and Pitsiou G, (2011) “Pneumococcal vaccination in adults: does it really work?” Elsevier, retrieved from, https://doi.org/10.1016/j.rmed.2011.07.008
Latifi-Navid, H., Latifi-Navid, S., Mostafaiy, B. et al. (2018) “Pneumococcal Disease and the Effectiveness of the PPV23 Vaccine in Adults: A Two-Stage Bayesian Meta-Analysis of Observational and RCT Reports”. Sci Rep 8, 11051. https://doi.org/10.1038/s41598-018- 29280-2
